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In mountainous lake areas, lake-land and mountain-valley breezes interact with each other, leading to an “extended lake breeze”. These extended lake breezes can regulate and control energy and carbon cycles at different scales. Based on meteorological and turbulent fluxes data from an eddy covariance observation site at Erhai Lake in the Dali Basin, southwest China, characteristics of daytime and nighttime extended lake breezes and their impacts on energy and carbon dioxide exchange in 2015 are investigated. Lake breezes dominate during the daytime while, due to different prevailing circulations at night, there are two types of nighttime breezes. The mountain breeze from the Cangshan Mountain range leads to N1 type nighttime breeze events. When a cyclonic circulation forms and maintains in the southern part of Erhai Lake at night, its northern branch contributes to the formation of N2 type nighttime breeze events. The prevailing wind directions for daytime, N1, and N2 breeze events are southeast, west, and southeast, respectively. Daytime breeze events are more intense than N1 events and weaker than N2 events. During daytime breeze events, the lake breeze decreases the sensible heat flux (Hs) and carbon dioxide flux ( $$\boldsymbol{F}_{\text{CO}_{2}}$$ ) and increases the latent heat flux (LE). During N1 breeze events, the mountain breeze decreases Hs and LE and increases $$\boldsymbol{F}_{\text{CO}_{2}}$$ . For N2 breeze events, the southeast wind from the lake surface increases Hs and LE and decreases $$\boldsymbol{F}_{\text{CO}_{2}}$$ . Results indicate that lakes in mountainous areas promote latent heat mixing but suppress carbon dioxide exchange.

Context Crescents have been noticed in pathologic changes in patients with diabetic kidney disease (DKD). However, the clinical significance of crescents is still not well recognized. Objective The main objective was to investigate the association between crescents and the prognoses of type 2 DKD (T2DKD) patients, and, secondly, to analyze the relationship between crescents and clinicopathologic features. Methods A retrospective cohort study of 155 patients with T2DKD diagnosed by renal biopsy was carried out in a single center. Clinicopathologic features of patients with or without crescents were analyzed. Cox regression models and meta-analysis were used to determine the prognostic values of crescents for T2DKD. A nomogram was constructed to provide a simple estimation method of 1, 3, and 5-year renal survival for patients with T2DKD. Results Compared with T2DKD patients without crescents, patients with crescents had higher 24-hour proteinuria and serum creatinine levels, as well as more severe Kimmelstiel–Wilson (K-W) nodules, segmental sclerosis (SS), and mesangiolysis (all P Conclusion Patients with crescents in T2DKD have more severe clinicopathologic changes and worse prognoses. The crescent can serve as an independent risk factor for T2DKD progression.

Wetlands are “hot spot” area of global climate change, which are obviously sensitive to climate change. Under climate change, the carbon sequestration potential and carbon balance over wetland ecosystems are greatly altered, and large uncertainties are still existed in carbon budgets over these areas. Tengchong Beihai wetland is the only highland “floating blanket” lake wetland which is located in Southwest of China. As this land surface is composed by both water and terrestrial land surface, it’s doubted whether this type of wetland behaves more like lake or the latter one. Based on one year continuous observation measured with eddy covariance technique over Beihai wetland and Erhai Lake in 2016, the patterns of CO2 flux and energy fluxes over Tengchong wetland and Erhai lake are analyzed. The results show the diurnal variation of H and LE are both similar to Rn, which is different with Erhai lake. Erhai lake has a higher evaporation rate even in nighttime, which is much larger than Beihai wetland, due to the “floating blanket” vegetation could obviously reduce the evaporation rate. Beihai wetland acts as CO2 sink for the most time of the year, with an annual CO2 flux of -202.2 g C m-2, while Erhai Lake acted as CO2 source with an annual CO2 flux of 143.7 g C m-2. The results indicate the carbon and water exchange process in Beihai wetland behaves more like vegetated land surface.

Large uncertainties exist in carbon sequestration and water exchange process in wetland ecosystems under climate change. Beihai wetland is a very rare special type of alpine marsh with plants floating on the water surface located in the southeast margin area of the Tibetan Plateau. Based on the eddy covariance measurements from July 2015 to December 2016 over Baihai wetland, we have investigated the patterns of energy and carbon dioxide fluxes between the air and the alpine marsh and their main drivers. The latent heat flux (LE) was the main consumer of available radiation which accounted for 63% of net radiation (Rn) in 2016. Rn was the main factor determining H at both wet and dry season. Air temperature (Ta) and vapor pressure deficit (VPD)were most influenced with half-hourly LE during both wet and dry season, and VPD showed a larger influence on NEE in dry season than that in wet season. The total evapotranspiration (ET) in wet season occupied 60% of annual ET with an amount of 762.3 mm yr−1 in 2016, which was much lower than the annual total precipitation (1780.2 mm yr−1). Photosynthetic active radiation (PAR) was the main controller in the half-hourly net ecosystem exchange (NEE), while Ta mainly controlled the seasonal variations in NEE. The annual total NEE, gross primary production (GPP) and ecosystem respiration (RE) were -233.8, 796.6 and 562.8 g C m−2 yr−1 in 2016. The fraction of vegetation to water surface changed from 66% to 74% in the study period. A positive linearly relationship was both found between the fraction of vegetation to water surface and CO2 uptake and evapotranspiration. The fraction of vegetation to water surface could explain 40% variation of ET and 62% variation of NEE, respectively.

In this paper, we study the medical team planning and scheduling in home healthcare within a weekly horizon, including the planning of nursing visits and the daily traveling route scheduling. Two objectives are considered: the first one is to minimize the total operation cost of the healthcare agency and the second one is to maximize the patient satisfaction. The problem is formulated as a mixed integer program, to seek for a trade-off between two objectives, with the characteristics of the patient requirements including nursing types, nursing frequency and service length considered. Medical team types, available service days and overwork penalty are also respected in the model. Then an $$\epsilon $$ -constraint method is adopted to obtain exact non-dominated solutions. To address large-scale problem instances, three heuristic approaches are developed to generate approximate Pareto fronts in a reasonable time. The set of non-dominated solutions are valuable for decision-making. Computational experiments are conducted and the results demonstrate the efficiency of the approaches.

The differences in planetary boundary layer characteristics, in particular atmospheric boundary layer height (ABLH), humidity, and local circulations in pre-monsoon and monsoon period over the Erhai Lake, were simulated by the lake-atmosphere coupled model WRF v3.7.1. No lake simulations were also conducted to investigate lake effects over complex topography. During pre-monsoon period, local circulation was fully developed under weak synoptic system. The ABLH ran up to 2300 m or so. During monsoon period, temperature difference between land and lake became smaller, resulting in weaker local circulations. The height of circulation reduced by 500 m, and ABLH ran up to 1100 m during the day. Enhanced soil moisture and low surface temperature due to monsoon rainfalls in July could be the main reason for the slightly lower ABLH over the Erhai Lake area. Specific humidity of the boundary layer increased 8.8 g kg−1 or so during monsoon period. The Erhai Lake enlarged thermal contrast between valley and mountain slope in the Dali Basin. The lake reduced air temperature by 2~3 °C during daytime and increased air temperature by nearly 2 °C in the evening. Due to its small roughness length and large thermal capacity, the Erhai Lake enlarged lake-land temperature difference and local wind speed. A cyclonic circulation was maintained by the combination of mountain breeze and land breeze in the south of the lake. The lake decreased air temperature, increased specific humidity, and reduced ABLH during daytime, whereas the opposite effect is presented at night.

Based on five years of eddy covariance measurements at multiple levels (47, 140, and 280 m) of Beijing's 325-m meteorological tower, the exchange process of CO2 fluxes between the atmosphere and urban surface were investigated. As a result of the total vehicle control policy from 2011 in Beijing, the growth rate of annual total CO2 flux at 140 m is 7.8% from 2008–2010 but 2.3% from 2010–2012. With the minimum vegetation cover and largest population density, the 5-yr average annual total CO2 flux at 140 m is largest (6.41 kg C m−2 yr−1), compared with that at 47 m (5.78 kg C m−2 yr−1) and 280 m (3.99 kg C m−2 yr−1). With regards to annual total CO2 fluxes in Beijing, vehicle numbers and population are the main controlling factors. The measured CO2 fluxes were highly dependent on land cover/use in the prevailing wind direction. The CO2 fluxes at three layers all correlated positively with road fraction, with the R2 values being 0.69, 0.57, and 0.54 (P 摘要 本文基于北京325米气象塔在47, 140, 和280米三层高度的5年涡动相关观测资料, 研究了城市下垫面与大气间的CO2交换过程.由于北京市2011年开始实行工作日汽车尾号限行, 140米高度CO2通量的年增长率由2008–2010年的7.8%降低到2010–2012年的2.3%.140米高度通量源区内植被比例最小且人口密度最大, 因此140米高度的5年平均CO2通量年总量)6.41 kg C m−2 yr−1(大于47米)5.78 kg C m−2 yr−1(和280米)3.99 kg C m−2 yr−1(.在年尺度上, 北京汽车总保有量和总人口是最重要的CO2通量控制因子.CO2通量随风向的变化主要与风向对应的通量源区内下垫面土地利用方式有关.三层高度的夏季CO2通量均与道路的比例呈正相关关系.47, 140, 和280米的决定系数分别为0.69, 0.57, 和0.54 (P

The cropland ecosystem in semiarid areas is sensitive to climate change. The accurate representation of crop phenology is important for predicting the carbon and water exchange process. The performance of a newly developed phenological model (SiBcrop) for simulations of carbon flux phenology in a semiarid area ecosystem was evaluated. The results showed that the SiBcrop improved the prediction for daily maximum gross primary production (GPP), and the days GPP reached the maximum value were closer to the observation, compared to SiB3. SiBcrop had a better prediction for both monthly total net ecosystem exchange (NEE) in the growing season than in the dormant season in semiarid areas. The day when the cumulative NEE predicted with SiBcrop became positive was closer to the observation. The observed start date of carbon uptake (CUstart) had a larger annual variation than did the end date of carbon uptake (CUend). SiBcrop had a better prediction for CUstart but poor for CUend, compared to SiB3. There was a longer carbon uptake period (CUP) predicted with SiBcrop than the observed results.

Lake evaporation is an important link connecting the water cycle and the surface energy cycle and remains one of the most uncertain terms in the local catchment&rsquo, s water balance. Quantifying lake evaporation and its variability is crucial to improve water resource management and understand the response of the lake system towards climate change. In this study, we evaluated the performances of nine evaporation methods at different timescales and calibrated them by using the continuous eddy covariance (EC) observation data during 2015&ndash, 2018 over Erhai Lake, a highland open freshwater lake situated in the Dali valley, China. The nine evaporation methods could be classified into combination methods (Bowen-ratio energy budget, Penman, Priestley&ndash, Taylor, DeBruin&ndash, Keijman and Brutsaert&ndash, Stricker), solar radiation-based methods (Jensen&ndash, Haise and Makkink) and Dalton-based method (mass transfer and Ryan&ndash, Harleman) based on their parameterization schemes. The Dalton-based Ryan&ndash, Harleman method is most suitable for estimating evaporation at daily to weekly scales, while the combination methods and solar radiation-based method had good estimates at monthly timescale. After calibration, the biases of the Jensen&ndash, Haise and Ryan&ndash, Harleman method were slightly reduced, while the biases of the Makkink and mass transfer methods were reduced substantially. The calibrated Jensen&ndash, Haise method with small annual bias (&minus, 2.2~2.8%) and simple input variables was applied to estimate the long-term trend of evaporation during 1981&ndash, 2018. The annual total evaporation showed an insignificant increasing trend of 0.30 mm yr&minus, 1, mainly caused by the significant rising air temperature. This study showed the performance of evaporation methods over water bodies had large discrepancies on different time scales, which indicated the importance of the choice of evaporation methods and provided instruction for water resource management of this region under climate change.

Lake Erhai is a subtropical highland shallow lake on southeast margin of Tibetan Plateau, which is influenced by both South Asian and East Asian summer monsoon. Based on four years continuous eddy covariance (EC) data over Lake Erhai, the monsoon effect on water–atmosphere exchange process is investigated by comparing the energy and CO2 fluxes patterns and their main drivers during pre-monsoon (March–April), monsoon (May–October) and post-monsoon (November–December) periods. The results show the atmospheric properties display a large difference for during three different periods. There is a negative difference between water surface and air temperature (ΔT) during pre-monsoon period, while a positive ΔT during post-monsoon period. The diurnal sensible heat flux (Hs) is larger during post-monsoon period, while the latent heat flux (LE) is larger during monsoon period. The monthly average Hs and heat storage (ΔQ) in the lake remain negative during pre-monsoon period and the early monsoon period, and they become positive in the middle monsoon period, which indicates that the lake absorbs heat at first and releases it subsequently. LE plays a dominating role in the energy partitioning of the lake. The Bowen ratio is higher during post-monsoon period. An uptake of CO2 flux is observed in middle of a day during monsoon and post-monsoon period. The ΔT is the main drivers for Hs and the effect of ΔT is increased as time scales are extended from half-hourly to monthly. The wind speed has a weak effect on Hs but a strong effect on LE and CO2 fluxes. Similar main drivers for Hs are found during pre-monsoon period and post-monsoon period, which is also found for CO2 flux, indicating a large impact of monsoon on the heat and carbon exchange process over Lake Erhai.

Phenology plays an important role in the carbon exchange process. Seven years of continuous eddy covariance data across two different ecosystems in a semiarid area were used to investigate the variation in phenology indices, its effect on the carbon exchange process, and responses to climate change. The results showed that there was large annual variation for vegetation phenology. The GSL (growing season length) displayed an obvious increasing trend for the grassland ecosystem during the 7 years, and it was most determined by SOS (the start day of growing season). The growing season was divided into three periods, the recovery period (S1), the stable period (S2), and the senescence period (S3). Both ecosystems had a similar ratio of Re (ecosystem respiration) to GPP (gross primary production) during S1 and S2 periods but a much larger Re/GPP ratio during the last growing period. The inter-annual variation of the peak rate was most responsible for the NEP (net ecosystem production) and its components (GPP and Re) in both ecosystems. The inter-annual variation of recovery rate, GSL and SOS was found to be closely correlated to Re for the grassland ecosystem, while that could not be found for the cropland ecosystem. The temperature in June was most closely correlated with the peak rate of GPP and NEP for grassland ecosystem, with a significant correlation coefficient of −0.90 and −0.82, respectively. Meanwhile, the precipitation in July was found to be closely correlated with GPP for both ecosystems, with a similar correlation coefficient of 0.83. The precipitation and temperature roughly exhibited an inverse effect on vegetation phenology in this semiarid area. The variation of temperature in the early month and precipitation in mid growing season showed a more significant effect on main phenology indicators for the cropland ecosystem than those for grassland ecosystem.

The planetary boundary layer (PBL) parameterization schemes play a critical role in the weather and climate models, while they describe physical processes associated with the momentum, heat and humidity exchange between land surface and atmosphere. The sensitivity of boundary layer variables to eight PBL parameterization schemes (three non-local and five local closure schemes), available in the Weather Research and Forecasting (WRF) model, is evaluated over the central Tibetan Plateau with field measurements of the Third Tibetan Plateau atmospheric scientific experiment (TIPEX III) in July. Model results showed acceptable behavior, but no particular scheme produced the best performances for all observation stations and meteorological parameters. All PBL schemes underestimated the surface temperature over the central Tibetan Plateau. The BouLac scheme showed the minimum cold bias of the surface temperature. For the surface energy budget components, it was found that the sensible heat flux and the downward longwave radiation were the main factors causing the lower surface temperature. The sub-grid scale gravity wave drag was added to reduce biases result from unresolved topography over the central Tibetan Plateau. It led to smaller cold bias, causing warmer lower-tropospheric temperature, smaller water vapor content and higher PBL height. The modified model results show more close to the observation.

This paper investigates quay crane scheduling problem at container ports, subject to arbitrary precedence constraint. Differing from traditional machine scheduling problems, non-crossing constraint must be satisfied because parallel quay cranes mount on a same rail to unload or load containers. Precedence relation in an arbitrary form is rarely investigated in the literature, however it may be originated from (i) reefers or dangerous cargo which requires high priority of processing, and (ii) yard stacking plan. We present computational complexity for several problem variations. We show the problem, even without precedence constraint, is strongly NP-hard, which improves the state-of-the-art. A genetic algorithm is proposed to obtain near-optimal solutions. Computational experiments demonstrate the efficiency.

Home healthcare is of great convenience to the patients and can also ease the overcrowded medical settings. The issue of paramedics arrangement is critical but still unsettled. Existing researches mainly focused on the assignment of single nurse, or daily multi-nurse scheduling. In this paper, we study the medical team planning problem in a weekly horizon, and the characters of each team including nursing type, skill level and number of nurses are considered. To jointly address these characters, we introduce patterns in our mathematical model. Moreover, nursing consistency is restricted in the constraints to improve patient satisfaction. Computational experiments are to be further conducted.

Evaluation of the WRF3.7.1 lake model performance on lake physical processes and lake-atmosphere interaction at Erhai Lake was conducted with in-situ observation data sets over the lake to verify the model results. The lake model with default parameters presented significant negative bias during the day and positive bias during the night on lake surface temperature. Calibrations of water absorption and extinction coefficients, surface roughness length and eddy diffusion coefficient were carried out to correct this bias. The added absorption and extinction coefficients increased solar radiation in upper water layer, leading to a little higher surface temperature. Compared to constant surface roughness lengths, parameterization of roughness lengths as functions of friction velocity and fetch length significantly improved simulations of lake surface temperature and sensible heat flux. In Erhai Lake, eddy diffusion coefficient of the Henderson-Sellers parameterization is smaller than that in deep lakes. The eddy diffusion coefficient was reduced by a factor of 0.05 in dry season and 0.02 in wet season respectively to restrict mixing strength, generating a reasonable diurnal range with observed surface temperature. The adjusted parameters simulations matched better with in-situ observations in diurnal cycle of temperature and surface heat fluxes, but still overestimated wind speed. Topographic correction is effective to correct the bias, indicating topographic correction over complex terrain was necessary.